Die-stock.



L. T. HAMMOND.

DIE STOCK.

APPLICATION FILED MARJZQ. IBIS.

1,209,960. Patented Dec. 26,1916.

' i 3SHEETS-SHEETI.

m: mwms PETERS 1:04 PNom-Llrna. WASNINGRIN. n c.

L. T. HAMMOND.

DIE STOCK.

APPLICATION FILED MAR. 29. I916.

1 99,960. Patented Dec. 26, 1916.

3 SHEETSSHEET 2.

L. T. HAMMOND.

DIE STOCK.

APPLICATION FILED MAR. 29. 1916.

1,209,960. Patented Dec. 26,1916.

3 SHEEP-SHEET 3.

1 PsrERs Co snow-Luna. wAskmcmN, u. c.

LORENZO T. HAMMOND, 0F COTUIT, MASSACHUSETTS.

DIE-STOCK.

Specification of Letters Patent.

Patented Dec. 26, 1916.

Application filed March 29, 1916. Serial No. 87,876.

T 0 all whom it may concern:

Be it known that I, LORENZO T. HAM- MOND, a citizen of the United States of America, anda resident of Cotuit, in the county of Barnstable and State of Massachusetts, have invented certainnew and useful Improvements in Die-Stocks, of which the following is a specification.

This invention relates to die stocks and particularly to devices of this character that are adapted for cutting tapered threads in pipes and has for its object the provision of means adjacent to the cutting tools for centering pipes of various sizes whereby a more perfect cutting operation is assured.

Where die stocks are. used with guide members located at some distance from the cutting tools the end of the pipe is liable to be moved sidewise during the thread cutting operation, and a very imperfect cutting of thethread results, said thread being shallow at some points and quite deep at other points. This difficulty is overcome by providing in addition to the usual pipe supports other centering devices adjacent to the cutting tools, which centering devices eifectually prevent any play of the pipe while the thread is being cut thereon.

The invention consists primarily in providing the die stock housing with centering devices adj ustably mounted therein adjacent to the thread cutting tools and in the path of movement of said cutting tools.

The invention further consists in certaln novel features of construction and arrange v ment of parts which will be fully understood by reference to the description of the drawings and to the claims hereinafter given.

Of the drawings, Figure 1 represents a plan of a die stock embodying the principles of the present invention. Fig. 2 represents a front elevation of the same. Fig. 3 represents a transverse vertical section of same on line 3-3 on Fig. 1. Fig. 4 represents a transverse vertical section of same on line 44 on Fig. 1. Fig. 5 represents a longitudinal vertical section of the same on line 5-5 on Fig. 1. Fig. 6 represents a transverse vertical section of the same on line 6-6 on Fig. 1, and Fig. 7 represents a transverse vertical section of the same on line 77 on Fig. 1.

Similar characters designate like parts throughout the several figures of the drawlugs.

In the drawings, 10 is an annular frame having a forward projection 11 at the front end of which is formed a nut 12 adapted to receive the threaded tubular hub 13 of a die stock housing 14. The frame 10 is provided with a plurality of radial slots 15 in each of which is mounted a member 16 adapted to be moved longitudinally therein. Each member 16 is provided with a transverse slot 17 in one face into which extends a curved rib 18 formed upon an annular plate 19 surrounding the hub of the annular frame 10 and held in position by means of a nut 29 threaded to the extreme end of said hub, as indicated in Fig. 5 of the drawings. Each curved rib 18 is eccentric to the axis 'of said frame 10, as indicated in Fig. 7 of the drawings. The ring 19 is provided with an outwardly extending projection 21, by which the ring 19 may be moved about the axis of the frame 10 to move the members 16 inwardly and outwardly as desired so that their inner ends will contact with any size of pipe on which it is desired to cut threads.

When a pipe has been positioned within the frame 10 and the members 16 have been forced into contact therewith by the movement of the annular plate 19 about its axis, the frame 10 is prevented from rotating about the pipe thus centered by means of the locking member 22 threaded to one of the members 16.

The outer end of the member 22 has pivoted thereto a .handle28 by which said threaded member 22 may be rotated about its axis and jammed against the periphery of the pipe being operated upon. Surrounding the forwardly extending portion 11 of the frame 10 is a ring 24 having a plurality of transverse depressions 25 in a portion of its periphery. Surrounding the ring 24 is an annular operating member 26 retained in position between the flanged end of the ring 24 and its opposite end by means of a plate 27 secured to said ring 24. This operating member 26 is provided with oppositely disposed hubs 28 adapted to receive the handles 29 by which the operating member 26 may be moved about the axis of the frame 10 in either direction. The operating member 26 has mounted therein a radial dog 30 the inner end of which is adapted to enter and coact with the depressions 25 in the ring 24. This dog is forced inwardly by means of a spring 31 surrounding the reduced shank 32 projectinglug 45 extending therefrom into of said dog, said shank having a milled end 33 by which the dog. 30 may berotatedin.

its hearing when it is desired'to change'the direction of movement of the ring 24. tension of the spring 31 is regulated by. meansiof the adjustable-member 34.- Whenthe dog is in the position indicated in Fig,

3 of the drawings, any movementf'of the" operating member 26 in the direction of the arrow a on said figure willcause the ring24 to bemoved'about the axis of' the frame 10 in the direction of'the arrow 6 on said figure. VVhe'n the operating member 26 is mo-ved'in the direction opposite to that indicated by the arrow 6;, the ring, 24- will remain at'a standstill and the dogSO will be moved out: wardly. against'the tension 'of the spring 31 until it engages with the wall of a-nother depression 25, after which a furthermovement .of the operating member 26'in'the direction of the arrow a will-transmitto the ring. 24 a further movement: of said ring therefore, that when the ring 24 is rotated in either'direction, the housing:14.will be simultaneously rotatedlinthesame direction; In view ofthefact that-the nut 12..upon the.

frame lOis held stationary. during the rotationofthering 24andfthe housing. 14, the rotation of thethreaded hub 13.0f the =housingwill cause said. housing. to. be moved toward or from the ring 24 accordingtoqthe direction in which said. ring is. being. ro tated.

The-housing.- 14 is. providedwith a plu rality of radial grooves 38 ineach of when.

is. mounted a cutting. tool or chaser. 391- Each cutting. tool: 39. is provided with a lateral lug 40 extending into a curved groove 41 formed in an annular plate 42 surround-f ing the forwardhub43 of.the housing.14.'.

The'curved grooves 41 are formedZin the plate 42 .eccentrically tothe axis ofthe housing. 14,. as. clearly shown inv Fig,. 6. ofth'e Bearing against :the outer face drawings, of the annular plate. 42. isanother annular plate .44 surroundinga hub 43andfjl1avinga an inclined-slot-46'. in one'ofthe arms 35' projecting forwardly from thering .344 The platesx42an-d 441are heldiinaposition upon the hub 43by means of anannular plate 47' secured: to. the: hub 43.. by means; of the screws..48..

The plate 42 is .providedfwitha radial ear 49 011 which is mounted a laterallythreaded stud 50 and a steady pin 51. Mounted upon the stud .50 and pinfelpis a.clamping plate 52",the end of which 'overlaps'the plate 44 and is adapted to be forced into gripping contact therewith by means of the nut 53 threaded to the;stud-;50. When the'plate 52is forcedinto gripping contact with the plate 44, the two" plates'42 "and 44 will rotate together.

The device as heretofore described is a well-known construction of die stock for cuttingjtapered threadsv in pipes. The 'diffi culty that: has been found" toexist in this form of pipe cutting device is that in the cuttingop eration the chasers" or. cutting tools 39' will force, the unsupported ends of the pipe laterally, and'thereby cause a very im' perfect cuttingj operation, the threads at some points being very shallow" and. at other points quite deep. Veryroften, owing to the imperfect'cutting of the threads, it is necessary/ to. out new threads; and sometimes an entire j ob is'spoiled by the imperfect opera- If the tion of the thread cutting device; pipeis used with the imperfect thread cut thereon, itis diflicultto keep the joint in the assemb'l'ed pipestight. The imperfect cuttingof the threads occurs more often in brass p'ipe'than in iron pipe, but'occurs to a V greater orless extent even in the latter. It is self-evident that it is desirable to overcome these objections, and. this is: accomplished by providing the housing 14 witha plurality of pipe centering devices' 54 ?'which extend radially into the interior'of saidhousing.,' These centering members 54'are adjacen't'to the chasers or cutting tools 39 and between them and'the supporting members 16. It'is obvious that when the centering.

devices 54 are provided in additiontothe supporting members 16, and the'former are located in close. proximity to the cutting" members or ch'asers 39, there can be no lateralmovement 'of'th'e unsupported end of the p1p,e;--

Durlng. the. rotation of "the housing "14 the inner. ends. of the members.54' will travel over the periphery of the pipeimmediately' inadvance of the cutting tools 39,- and asa consequence of this contact between the in-.

nerends-offsaid centeringdevices 5'4 of the periphery ofthepipfe, the samedepth of teetlfiwill 'be insured throughout the cutting operation. 7

The members 54g-extend flthrough radial openings. 55" in the -h'ousing- 14, and each 1 is provided withsalug. or projection 57 extendinginto. eccentric grooves 58 formed in tlieannular. plate 59 set into a recess 60 in therear face of'the housing '14: The plate- 591s provided with ahan'dle {61 'by which the said plate may be rotatedin either directionabouttheaxis of the housing 14. Displace ment,.of the plate59 from the recess 60 may be prevented in any w'ell known mannersuch as by means of the clips 62 secured to tlie housing 1i and extending over the outer face of said plate.

Secured to the rear face of the housing 1 1 is a threaded stud 63 on which is mounted a clamping nut 64 adapted to bear against the face of the plate 59 and lock it in its adjusted position. When the cutting device has been placed upon a pipe into the periphery of which it is desired to cut a thread, the supporting members 16 are adjusted so that their inner ends bear firmly upon one portion of the pipe and the locking member 22 is then adjusted so that the rotation on the pipe of the frame 10 is prevented. The centering members 54: are then moved into contact with the periphery of the pipe at its extreme outer end and then the plate 59 is locked in its adjusted position by means of the clamping member 64. The chasers 39 are adjusted for the proper size of pipe and are locked in their adjusted positions by means of the clamping devices 5253. When these adjustments have been made the operation of cutting the threads in the pipe is effected in the same manner that the threads would be cut by the device before the present improvements had been applied thereto.

It is believed that the operation and many advantages of this invention will be fully understood from the foregoing description.

Having thus described my invention, I claim:

1. In a device of the class described, the combination of a housing; a plurality of radial cutting tools therein; means for adj usting said tools for different sizes of pipes; a plurality of radial pipe centering devices mounted in said housing adjacent to said cutting tools; means for adjusting said centering devices for various sizes of pipes; means for rotating said housing; and means for continuously moving said cutting tools outwardly during the rotation of said housing.

2. In a device of the class described, the combination of an annular frame; means for centering a pipe therein; means for clamping said frame to said pipe; a nut secured to said frame; a housing provided with a tubular portion threaded to said nut; means for rotating said housing; a plurality of radial cutting tools mounted in said housing; a plurality of radial centering devices also mounted in said housing between said cutting tools and said threaded tubular portion; independent means for adjusting the positions of said cutting tools and centering devices; and a locking device for each adjusting means.

3. In a device of the class described, the combination of an annular frame; means for centering a pipe therein; means for clamping said frame to said pipe; a nut secured to said frame; a housing provided with a tubular portion threaded to said nut; means for rotating said housing; a plurality of radial cutting tools mounted in said housing; a plurality of radial centering devices also mounted in said housing between said cutting tools and said threaded tubular portion; independent means for adjusting the positions of said cutting tools and centering devices; a locking device for each adjusting means; and means for constantly moving said cutting tools outwardly during the rotation of said housing.

Signed by me at 4 Post Office Sq., Boston, Mass, this 28th day of March, 1916.

' LORENZO T. HAMMOND. Witnesses:

WALTER E. LoMBARD, NATHAN C. LOMBARD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

